It's no secret that Google likes speed. They have made several announcements about the importance of speed on the web and go so far as to describe themselves as "obsessed with web speed". In April 2010, they announced that Google search was including a new signal in their search ranking algorithms: site speed.

"Historically, we haven't had to use it in our search rankings, but a lot of people within Google think that the web should be fast," says Matt Cutts, Google Software Engineer. "It should be a good experience, and so it's sort of fair to say that if you're a fast site, maybe you should get a little bit of a bonus. If you really have an awfully slow site, then maybe users don't want that as much."

To this end, Google has released a web performance tool commonly called "Page Speed". There are actually several tools related to performance profiling of web pages. According to the Google overview:

"The Page Speed family consists of several products. Web developers can use the Page Speed extension for Firefox/Firebug to analyze performance issues while developing web pages. Apache web hosters can use mod_pagespeed, a module for the Apache™ HTTP Server that automatically optimizes web pages and their resources at serving time. "

Google Page Speed is an open source Add-on for Firefox and Firebug. This add-on will help you analyze deeply your website/blog in order to improve its performance and crawling process. The performance tool not only evaluates the performance of web pages, it will also provide suggestions on performance improvement. It performs several tests on a site's web server configuration and front-end code. These tests are based on a set of best practices known to enhance web page performance. Webmasters who run Page Speed on their pages get a set of scores for each page, as well as helpful suggestions on how to improve its performance. It is also Google's preferred environment for introducing new performance best practices.

In the June 04, 2009 introduction of Page Speed, Richard Rabbat and Bryan McQuade (on the Page Speed Team) stated:

Page Speed automatically optimizes images for you, giving you a compressed image that you can use immediately on your web site. It also identifies issues such as JavaScript and CSS loaded by your page that wasn't actually used to display the page, which can help reduce time your users spend waiting for the page to download and display.

Page Speed's suggestions are based on a set of commonly accepted best practices that we and other websites implement. To help you understand the suggestions and rules, we have created detailed documentation to describe the rationale behind each of the rules. We look forward to your feedback on the Webmaster Help Forum.

One of the tools in the family is called "mod_pagespeed". It is designed to perform on-the-fly optimization in the Apache™ 2 HTTP Server. It applies Page Speed performance best practices automatically. Google says, "Webmasters can get the benefits of the optimizations without having to manually going back and fixing the performance issues that Page Speed detects."

Page Speed has an SDK that Google provides in order to encourage integrating its performance testing analysis and suggestions into other testing tools. The SDK is a C++ library that can be used with your server environment to automatically optimize your web pages and their resources.

I found this in a comment stream that I found interesting too: "Page Speed is the same tool as YSlow but with few differences. Steve Souders the creator of YSlow is now emplyed at Google. This is why both tools have the same features."

RustyBrick.com has this to say of the Page Speed tool:

The performance analyzer runs a bunch of tests on all resources of a website such as html, JavaScript, CSS, and image files. It checks or estimates the compression or compactness possibilities of files, inspects the HTTP headers, and suggests improvements in order of priority (or usefulness). After it reports about the areas of your website where performance can be best increased, you can read about the best practices to find out how to implement them.

Another nice feature is that it automatically minifies your JavaScript and CSS into separate files, and calculates the size difference in kB and percentages. You may then choose to replace the larger versions.

The activity timeline records and displays events during and after the page load process, showing you exactly when an event occurred and for how long. I didn't find this timeline as useful as Firebug's own Net graph that also provides time and detailed information on each resource, and that allows you to inspect the headers for each request/response pair.

Google's Webmaster Central Blog says, "...faster sites don't just improve user experience; recent data shows that improving site speed also reduces operating costs. "

This web performance tool is worth a try. By making individual pages faster, then your load testing should be better because the efficiencies will probably keep your site running under a higher load of concurrent users.